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Comment Re:does it run Linux - yea but it is "boring" (Score 4, Informative) 326

The current limit on Linux (with 2.6 series) is 8192 CPUs on POWER and 4096 on x86. And there are even a number of non-x86 machines today that reach these sizes in a cache-coherent (ccNUMA) manner that Linux works well on. You still have to be careful with application design, though, because it's fairly easy to hit bottlenecks either in the application or in the kernel that will limit scalability. Most common workloads are already seeing
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"Tube Map" Created For the Milky Way 142

astroengine writes "Assuming you had an interstellar spaceship, how would you navigate around the galaxy? For starters, you'd probably need a map. But there's billions of stars out there — how complex would that map need to be? Actually, Samuel Arbesman, a research fellow from Harvard, has come up with a fun solution. He created the 'Milky Way Transit Authority (MWTA),' a simple transit system in the style of the iconic London Underground 'Tube Map.' (Travel Tip: Don't spend too much time loitering around the station at Carina, there's some demolition work underway.)"

Comment Re:Security enhancement at best (Score 2, Insightful) 59

It just means the clone will have to be a bit more expensive.

Cloned tags aren't using the same cheap chips that the common passive tags do. An attacker can afford to carry batteries with him and make the tag completely locally powered. Then he has much more powerful electronics at his disposal and can simulate whatever frequency response the original tag had due to its cheap (few cents per tag) design.

This fingerprinting will do no more than to force the attacker to pay a few bucks more to create a clone.

Comment Wrong assumptions (Score 5, Insightful) 444

The article assumes that when within a RAID5 array a drive encounters a single sector failure (the most common failure scenario), an entire disk has to go offline, be replaced and rebuilt.

That is utter nonsense, of course. All that's needed is to rebuild a single affected stripe of the array to a spare disk. (You do have spares in your RAID setups, right?)

As soon as the single stripe is rebuilt, the whole array is again in a fully redundant state again - although the redundancy is spread across the drive with a bad sector and the spare.

Even better, modern drives have internal sector remapping tables and when a bad sector occurs, all the array has to do is to read the other disks, calculate the sector, and WRITE it back to the FAILED drive.
The drive will remap the sector, replace it with a good one, and tada, we have a well working array again. In fact, this is exactly what Linux's MD RAID5 driver does, so it's not just a theory.

Catastrophic whole-drive failures (head crash, etc) do happen, too. And there the article would have a point - you need to rebuild the whole array. But then - these are by a couple orders of magnitude less frequent than simple data errors. So no reason to worry again.

*sigh*

Comment Re:Huh? (Score 1) 951

Indeed, the term Darwinism is mainly used by Creationists, the same way that Allopathy is a term coined by practitioners of Homeopathic medicine.

And the reason for that is because creating such a duality makes it seem that both approaches are equally valid. I'm sure there are many more examples ...

Comment Re:Fuel economy (Score 1) 1114

Not true.

If you're going downhill, on any modern car the best is to shift into a high gear (4-6th, depending o the speed you're going downhill), such that you engine is running barely above idle RPM.

Then, the ECU will shut off the fuel supply altogether, and basically go into engine braking mode instead of keeping the engine in rotation by supplying it with a trickle of fuel. The braking effect in 6th gear is however minimal and thus even a very small slope is enough to keep the car going at a constant speed.

Super-ATMs Being Rolled Out 270

News.com has an article up looking at something I find interesting and somewhat confusing. The Vcom ATM is an attempt to make people's lives more convenient by adding unexpected functionality to the standard Teller Machine. Besides dispensing cash, new ATMs can fulfull the roles of PayPal (by sending money to people), bank (by cashing checks on the spot), and cellphone store (by selling Verizon services). From the article: "The Circle K and Exxon Mobil machines are far more basic than 7-Eleven's Vcoms, which have been called overengineered. Several dozen customers polled informally outside a 7-Eleven in Winter Springs, Fla., recently said that they had never used the Vcom inside, and one woman who said she did use it once to withdraw cash complained that it was 'confusing' and 'complicated,' and added that she would not use it again. 'There were just too many steps,' said the woman, Peggy Baker, who teaches French in Winter Springs. 'And the $1.75 transaction fee was too much--it was painful.' She said she was not interested in the other Vcom features, which require users to enroll and enter a Social Security number on a touch screen."

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